This application claims the priority of Austrian Patent Application Serial No. GM 514/2000, filed Jul. 13, 2000, the subject matter of which is incorporated herein by reference.
The present invention relates, in general, to a machine for removing an old track and laying a new track composed of rails fastened to ties supported on ballast.
U.S. Pat. No. 4,854,243 discloses a track renewal machine for removing an old track and laying a new track, which includes a machine frame extending in a longitudinal direction and supported on the track by undercarriages for mobility in an operating direction. Mounted on the machine frame between the undercarriages is a tie lifting device for raising old ties and a tie laying device for laying new ties. A tie conveyor unit extends in the longitudinal direction. A clearing device in the shape of an endless clearing chain is provided between the tie lifting device and the tie laying device and serves to take up ballast from the track. The tie conveyor unit for transporting ties is positioned in such a way that it extends through said clearing chain. For reasons of space availability, the ties placed on the tie conveyor unit must be positioned so as to extend in the longitudinal direction in order to enable them to be moved through the chain. The end of the tie conveyor unit is located immediately in front of the tie laying device.
It would be desirable and advantageous to provide an improved track renewal machine which is so configured as to obviate prior art shortcomings and to allow transport of ties in the region between the tie lifting and the tie laying device in such a way as to leave sufficient space for placement of additional working units.
According to one aspect of the present invention, a machine for removing an old track and laying a new track composed of rails fastened to ties supported on ballast, includes a machine frame extending in a longitudinal direction and supported on the track by undercarriages for mobility in an operating direction; a tie lifting device, mounted on the machine frame between the undercarriages, for raising old ties; a tie laying device, mounted on the machine frame between the undercarriages, for laying new ties; and a tie conveyor unit extending in the longitudinal direction and including a first conveying section, having a tie receiving end positioned ahead of the tie laying device in the operating direction and a transfer end positioned behind the tie laying device, and a second conveying section, positioned underneath the first conveying section, for receiving ties from the transfer end, wherein the second conveying section has a delivery end positioned immediately behind the tie laying device in the operating direction.
In accordance with the present invention, the ties can now be positioned parallel to the longitudinal direction during the entire transport path through the region between the tie lifting device and the tie laying device, up to the point where the ties must be turned into the final transverse position extending perpendicularly to the longitudinal direction. As a result, a maximum of space for installing further working units remains available between the tie lifting and tie laying devices. An increase in distance between the tie lifting and tie laying devices is therefore not necessary. Advantageously, the track-less construction gap located between the tie lifting device and the tie laying device can thus be utilized for taking up the soiled or contaminated ballast by means of -a clearing chain, and for discharging as well as grading and compacting cleaned ballast. The conveyor belts required for this purpose can also be arranged in this space without problems due to the particular design of the tie conveyor unit.
According to another aspect of the present invention, a machine for removing an old track and laying a new track composed of rails fastened to ties supported on ballast, includes a machine frame extending in a longitudinal direction and supported on the track by undercarriages for mobility in an operating direction; a tie lifting device, mounted on the machine frame between the undercarriages, for raising old ties; a tie laying device, mounted on the machine frame between the undercarriages, for laying new ties; a tie rotating device, mounted on the machine frame, for swivelling ties into a position extending in the longitudinal direction; and a tie conveyor unit extending in the longitudinal direction and including a first conveying section, having a tie receiving end positioned ahead of the tie lifting device in the operating direction and a transfer end positioned ahead of the tie lifting device, and a second conveying section positioned underneath the first conveying section and having a receiving end positioned immediately ahead of the tie lifting device in the operating direction.